Calculate Volume

[Sentinel]

Len Dia Vol
4.00 1.00 2.73
4.00 0.75 1.57
6.00 1.00 4.01

These are test values, I need to find the volume of a cylinder for this CAD project, meaning:

Vol = 3.14 (Pi) * r^2 * L (Height)

But my teacher has Volume listed as 2.73 (inches cubed) and if you put those values in for volume they work out to something like 12.6

How is this working? Any ideas?

 

[chuckywang]

Units?

 

[Sentinel]

inches

 

[ElFenix]

well multiplying 3.14 by pi doesn't help.

 

[Sentinel]

im saying Pi which rounded off is 3.14

 

[radioouman]

find the area then multiply by length.

 

[dighn]

you aren't using the diameter as r are you?

 

[ElFenix]

well the first one should be pi, if i'm doing this right

 

[dighn]

Originally posted by: ElFenix
well the first one should be pi, if i'm doing this right

all of those volumnes seem to be wrong

 

[Toastedlightly]

Pir^2 x h

so r^2 = .5^2 = .25

.25 x 3.14 x 4 = 3.14

hmm

 

[PurdueRy]

yes none are right...but neither are you with your 12.6

 

[Colt45]

pi r^2 h is right

 

[FlyLice]

9870 in^5

 

[Sentinel]

ok if you are given

Len Dia
4.00 1.00

And it equals: 2.73

This is what I am supposed to figure out, with the given information, get the answer to volume...

 

[wbresson]

every post above here is right, every post below here is wrong

 

[jagec]

Originally posted by: wbresson
every post above here is right, every post below here is wrong

wbresson is quite possibly the coolest member of ATOT.

 

[Sentinel]

bump for more? cmon night crew...

 

[dighn]

those numbers are really off, there's something you aren't telling us or something

all those values seem to be off by a factor of 1/1.15. some kinda unit coinversion?

 

[Sentinel]

i will post the actual problem on the website

 

[smc13]

Start with the basics. The formula is height X radius squared X pi. You are given a diameter so you need the conversion formula. radius is one half diameter. once you have formulas you plug in the numbers and chug the result.

r=1/2 or .5

Vol=4*.5*.5*pi
Vol=2*.5* pi (I am just showing math you don't really need this step)
Vol= pi

 

[Sentinel]

Text

 

[Pepsi90919]

if Pi is equal to 3.14 then 0.999... would be equal to 1 which is CLEARLY wrong.

Discuss.

 

[Sentinel]

negative, Pi doesn't have to be exact it just has to figure the equation, here 3.14159265 if it makes you feel better

 

[A5]

It's not equal; it's just an approximation that's close enough for most use.

/discussion.

 

[Toastedlightly]

Well there seems to be inner and outer diameters?